644 ” MR. HARPER PEASE ON THE [ Dec. 9, 
the sternum, costal process, and the underside of the marginal shield 
is white, there being two small round black spots on the underside 
of each of the five front marginal shields. The head and neck are 
beautifully marked with very regular pale streaks, but there is no spot 
behind the eye, and no ring round the margin of the ear. This in- 
dicates the existence of a very distinct species; and Dr. Giinther thinks 
that it is the young state of the Emys grayii, which he has lately de- 
scribed (see antea, p. 504) from the adult shell, without the animal. 
The Mauremys fuliginosa (anted, p. 500) has the markings on 
the head and neck somewhat similar to those of Hmys flavipes, but 
sufficiently distinct to define this species, which is also at once known 
by the depressed and nearly uniform black shields of the shell. 
12. On the Classification of the Helicterine. 
By Harper Pxass, C.M.ZS. 
From a history of the genus Helicter which I published in this 
Society’s ‘ Proceedings’ (1862, p. 3) it appears that it was first 
named and described by Férussac in 1821 *, and that this term con: 
sequently takes precedence of Achatinella (Swains.), 1828t. 
I now propose to elevate it to the rank of a subfamily, and to dis- 
tinguish the several groups of species which it comprises by generic 
names. They are as distinct, as strictly definable, and vary even 
more widely than those of any other subfamily of land shells, From 
the difference in their habits and stations, we may also expect to find 
the animals to vary correspondingly when examined. = 
Had the several species been received in Europe at different times 
without their locality being known, they would have been distributed 
over five or six old established genera. They are, in fact, a natural 
subfamily, confined to the Hawaiian Islands, representing within 
themselves, by the forms of their shells, several genera inhabiting 
distant localities, in a similar manner to several other genera inhabit- 
ing Polynesia, such as Pitys, species of which have been classed by 
authors with the European genus Patula, although the animals. of 
the two are widely distinct. I will not notice at present the several 
attempts made of late years to dismember the Helicterine and unite 
several species to foreign genera, such as Balea and others, as I am 
convinced that the ‘‘Testaceous classification”? adopted by those 
authors will be abandoned so soon as the result of the researches of 
persons now permanently located at many localities in the tropics and 
elsewhere, formerly but rarely visited and hastily explored, are made 
known. 
As to the distribution of genera and species over the several islands 
of the group, I remark generally that, with the exception of the 
genus Leptachatina (the species of which are small and of simple 
* Tableau Syst. des An, Mollusques, 1821, p. 56; Voy. par M. de Freycinet, 
1824, p. 475. 
+ Quarterly Journal of the Royal Institution, 1828, p. 81. 
